Retainer for overmolded electrical circuit

ABSTRACT

A device configured to maintain an electric circuit in a fixed position during an overmolding process comprises a wire retainer configured to hold the electric circuit taut an in a fixed position while being molded within a molded item. The retainer has a first end and an opposite second end, and includes a first bushing defining a mounting hole for the molded item extending along a width axis. The built-in bushing includes front and back surfaces configured to be aligned and substantially co-planar with the front and back surfaces of the molded item. The device also includes a first securing member configured to secure a portion of the electric circuit to the retainer within the molded item, to hold the electric circuit in a fixed position within the molded item during the overmolding process.

FIELD OF THE INVENTION

The present invention relates to a retainer for use in overmolding anelectrical circuit, and more particularly to a retainer designed to holdthe circuit taut and in a fixed position during overmolding of thecircuit.

BACKGROUND OF THE INVENTION

It is well known to encapsulate components within a die mold cavity byrigidly affixing the components to or through the walls of the cavity.It some cases it is also desirable to avoid the visibility of fixing orholding devices at the surface of the molded item by providingretractable holding devices which retract either out of the moldingcavity or into the molded product while the molding material is “settingup.” Such devices and techniques, however, often do not hold theencapsulated component sufficiently taut and in a precisely definedposition. In some applications, for example, the molded components mustmaintain precise positions relative to other molded components or withrespect to the exterior surfaces of the molded item. Additionally, someknown techniques involve the use of retractable locator pins to holdwires and/or cables in fixed positions during molding processes, leavingbehind holes in the molded item upon their retraction which can reducethe integrity of the molded item.

The problem of precisely positioning components within a die mold cavitycan be further complicated by two additional factors. If the componentto be encapsulated is not rigid, holding it taut and in a fixed positionbecomes much more difficult. Additionally, the size and shape of themolded item may be such that very little clearance exists forpositioning the molded components away from the interior surfaces of thedie mold (and thus the exterior surfaces of the molded item). If thecomponents are not precisely and firmly positioned in the interior ofthe molding cavity, some of the components may be visible at or evenextend through the exterior surfaces of the molded item. Such componentbreakout may be grounds for rejecting the product. In the specific caseof wires and/or cables, without properly and sufficiently maintainingthe wires and/or cables in fixed positions, they often will float orshift during the molding process which may result in the wires and/orcables being visible at the exterior surfaces of the molded item.

Additionally, typical molding processes often produce molded items whichare difficult to mount because the processes have provided no suitablemechanism to mount the items.

There is therefore a need for a retainer for an overmolded electricalcircuit. The present disclosure is directed toward devices and methodswhich meet these needs.

SUMMARY OF THE INVENTION

In one aspect of the present disclosure, a device configured to maintainan electric circuit in a fixed position during an overmolding processcomprises a wire retainer configured to hold the electric circuit in afixed position while being molded within a molded item. The retainer hasa first end and an opposite second end, and includes a first bushingdefining a mounting hole for the molded item extending along a widthaxis. The built-in bushing includes front and back surfaces configuredto be aligned and substantially co-planar with the front and backsurfaces of the molded item. The device further includes a firstsecuring member configured to secure a portion of the electric circuitto the retainer within the molded item to hold the electric circuit in afixed position within the molded item during the overmolding process.

In another aspect of the present disclosure, a plug assembly comprises amolded plug, a retainer, first and second wire sets and first and secondsecuring members. The molded plug includes opposing first and secondends and opposing front and back surfaces, with the plug extending alonga longitudinal axis. The plug includes a socket extending from the frontsurface at least partially through the plug along a width axis, with thesocket defining at least two holes extending therethrough. The retaineris at least partially molded within the plug, and has a first endadjacent the first end of the plug and a second end adjacent the secondend of the plug. Additionally, the wire sets extend into the plug andare connected to the socket within the plug. The first securing membersecures the first wire set to the retainer within the plug, adjacent thefirst end of the retainer, and the second securing member secures thesecond wire set to the retainer within the plug, adjacent the second endof the retainer. The securing members hold the first and second wiresets in fixed positions within the plug during the overmolding process.

In yet another aspect of the present disclosure, a method comprisesproviding an electric circuit and providing a retainer configured tohold the electric circuit taut and in a fixed position within a cavityof a molding die during overmolding of a portion of the electric circuitto form a molded item. The retainer includes at least one built-inbushing defining a hole extending through the retainer. Additionally,the retainer is configured to remain permanently molded within themolded item. The method further comprises permanently attaching theelectric circuit to the retainer with at least one securing member andovermolding at least a portion of the electric circuit and the retainerto form the molded item containing a portion of the electric circuit andthe retainer.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of components of a molded assemblyaccording to an embodiment of the present invention.

FIG. 2 is a perspective view of a molded assembly according to anembodiment of the present invention, with one component shown astransparent to enable visibility of other components.

FIG. 3 is a perspective view of the molded assembly according to theembodiment of FIG. 2.

FIG. 4 is perspective view of components of the molded assemblyaccording to the embodiment of FIG. 2.

FIG. 5 is a side, partial cross-sectional view of the molded assemblyaccording to the embodiment of FIG. 2.

DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

For the purposes of promoting an understanding of the principles of thedisclosure, reference will now be made to the embodiments illustrated inthe drawings and specific language will be used to describe the same. Itwill nevertheless be understood that no limitation of the scope of thedisclosure is thereby intended, and alterations and modifications in theillustrated systems, and further applications of the principles of thedisclosure as illustrated therein are herein contemplated as wouldnormally occur to one skilled in the art to which the disclosurerelates.

The present disclosure is directed to an assembly including a retainerdesigned to hold an electric circuit taut and in a fixed position duringovermolding of the circuit. The electric circuit is attached to theretainer via a securing member, such as a wire tie as an example. Theretainer and the electric circuit may be molded within a mold cavity ofa die to form a molded plug. Additionally, the retainer includes atleast one built-in bushing defining a hole through the retainer and themolded plug to allow for mounting of the plug.

Referring generally to FIGS. 1-5, there is shown an embodiment of anassembly 10 including an electric circuit 12 and a retainer 14 moldedwithin a plug 16. Retainer 14 is configured to hold electric circuit 12taut and in a fixed position during the overmolding process to createplug 16. In the illustrated embodiment, securing members such as wireties 18 are used to attach electric circuit 12 to retainer 14.Additionally, assembly 10 includes a socket 30 operably connected withcircuit 12 to form the electric plug component of plug 16. Forillustration purposes, plug 16 is shown as transparent in FIG. 2 tobetter illustrate the various other components of assembly 10; however,it should be appreciated that plug 16 may or may not be transparent.Additionally, plug 16 is absent from FIG. 1 as the remaining componentsmay be molded within various other items, as discussed below.

In the illustrated embodiment, electric circuit 12 includes two wiresets 26 and 28 entering plug 16 at opposite ends and extending to socket30. In certain embodiments, wire sets 26 and 28 each include a cable orouter sheath surrounding wires 29. As illustrated, there may be two suchwires 29 positioned in each cable. However, it is contemplated thatthere may be more or less wires within electric circuit 12 as wouldoccur to one skilled in the art. It should be appreciated that electriccircuit 12 can be otherwise configured with various other electricalcomponents, only one of the numerous possible examples beingillustrated.

Socket 30 includes a front end 30 a, a back end 30 b and extends along awidth axis Ws from outside of plug 16 at least partially therethrough.As illustrated, wires 29 within wire sets 26 and 28 may extend to and beelectrically connected with back end 30 b of socket 30. Socket 30defines holes 31 in front end 30 a which extend at least partiallythrough the socket and are configured to receive electrical connectors.In certain embodiments, the number of holes 31 in front end 30 aparallels the number of wires 29 within plug 16. Accordingly, in theillustrated embodiment, there are four holes 31 corresponding to thefour wires 29. Additionally, socket 30 may be connected to a componentof system 10, such as retainer 14 as an example. Accordingly, socket 30may be secured to retainer 14 via fasteners such as screws or bolts.

Retainer 14, as best illustrated in FIG. 2, may include a first built-inbushing 60 adjacent a first end 14 a and a second built-in bushing 62adjacent a second end 14 b. Bushings 60 and 62 define holes 61 and 63,respectively, extending through retainer 14 and plug 16 along width axisW_(H). Holes 61 and 63 are configured to receive mounting fasteners suchas mounting bolts 70 and 72 as examples (see FIG. 3) to mount plug 16.Built-in bushings 60 and 62 include front surfaces 60 a and 62 a andback surfaces 60 b and 62 b, respectively. In the illustratedembodiment, retainer 14 includes a longitudinal portion 66 extendingbetween bushings 60 and 62 along a longitudinal axis L_(R). In certainembodiments, longitudinal axis L_(R) of longitudinal portion 66 may besubstantially perpendicular to width axis W_(H) of holes 61 and 63.Additionally, in the illustrated embodiment, the widths of bushings 60and 62 are substantially equal and are larger than the width oflongitudinal portion 66, such that portion 66 is of reduced-height.However, it should be appreciated that retainer 14 can be shaped andsized differently, with only one example configuration being illustratedin the accompanying figures. In certain embodiments, retainer 14 iscomposed of a plastic material. However, retainer 14 may be made fromother materials as desired or deemed necessary.

Plug 16 includes a first end 16 a, a second end 16 b and extends along alongitudinal axis L_(P). As illustrated, retainer 14 may be moldedwithin plug 16 such that first end 14 a is positioned adjacent first end16 a and second end 14 b is positioned adjacent second end 16 b.Additionally, longitudinal axis L_(P) may be aligned with longitudinalaxis L_(R) of longitudinal portion 66 of retainer 14. Plug 16 includes afront surface 40, a back surface 42, a first end surface 44 and a secondend surface 46. As illustrated, socket 30 may extend from retainer 14out front surface 40 of plug 16 to allow access to the socket by a user.Additionally, front surfaces 60 a and 62 a of bushings 60 and 62 may bealigned and coplanar with front surface 40 of plug 16, and back surface60 b and 62 b of bushings 60 and 62 may be aligned and coplanar withback surface 42 of plug 16, such that the bushings define mounting holesextending through the plug to allow for mounting of the plug as desired.In the illustrated embodiment, end surfaces 44 and 46 define entranceholes 48 and 50 molded about wire sets 26 and 28, respectively. However,it should be appreciated that components of electric circuit 12 mayenter plug 16 at other locations as would occur to one skilled in theart. Plug 16 may optionally include a raised front portion 32 alongfront surface 40. In such embodiments, front end 30 a of socket 30extends through raised front portion 32 to allow access to the socket,as best viewed in FIG. 5.

Wire ties 18 may be used to secure wire sets 26 and 28 to retainer 14adjacent built-in bushings 60 and 62 along longitudinal portion 66, asbest seen in FIG. 4. In other embodiments, electric circuit 12 can besecured and held in place via wire crimps, wire clips, pieces of tape orvarious other securing members as would occur to one skilled in the art.In the illustrated embodiment, electric circuit 12 is secured toretainer 14 at two locations via two securing members. However, itshould be appreciated that electric circuit 12 could be secured toretainer 14 in other manners, at other locations, and through the use ofmore or less than two securing members.

Referring generally to FIGS. 1-5, the methods and operations involvingsystem 10 will be described hereafter. Electric circuit 12 is initiallysecured to retainer 14. In certain embodiments, circuit 12 may bepermanently secured to retainer 14. Circuit 12 may be secured via wireties 18 as described above; however, as previously noted, electriccircuit 12 may be secured to retainer 14 in various other manners aswould occur to one skilled in the art. Wire sets 26 and 28 may bepositioned such that they are generally aligned with retainer 14, withwire set 26 adjacent first end 14 a and wire set 28 adjacent second end14 b. Additionally, wires 29 within wire sets 26 and 28 may be operablyconnected with back end 30 b of socket 30 either before or after circuit12 is secured to retainer 14. Optionally, socket 30 may also be securedto retainer 14 as described above.

The electric circuit 12 secured to retainer 14, along with socket 30,are then placed within the mold cavity of a typical die mold (notshown). In certain embodiments, the die mold includes upper and lowerdie mold components. Wire sets 26 and 28 may extend into the die moldcavity, accordingly having portions positioned within the die moldcavity and portions positioned outside of the cavity. The die moldcomponents are configured to form a molded item, such as the illustratedplug 16. It is contemplated that various other molded items could becreated utilizing retainer 14. Additionally, the die mold may beconfigured such that front end surfaces 60 a and 62 a and back surfaces60 b and 62 b of bushings 60 and 62 contact inner surfaces of the diemold components, so that the bushings define holes in the molded plug tomount the plug via mounting fasteners. In certain embodiments, the diemold may also be configured such that a portion of socket 30 extends outof the die mold cavity so that the same portion extends out the frontsurface of the molded item.

Upon proper positioning of the components within the mold cavity, thecomponents are then overmolded to create a molded item. In certainembodiments, the upper and lower die mold components are broughttogether and a molten plastic material is injected into the die moldcavity according to a typical molding process. In certain embodiments, apolyvinylchloride material is injected into the die mold cavity,creating a molded item such as plug 16 composed of polyvinylchloride.However, it is contemplated that other materials and/or compositionsthereof may be used as desired in creating molded plug 16. Asillustrated, the die mold forms the molded plug 16 with wire sets 26 and28 extending into molded plug 16 and forming entrance holes 48 and 50 asa result of the molding process.

Molded plug 16 may be mounted by inserting mounting fasteners such asbolts 70 and 72 through holes 61 and 63 defined by built-in bushings 60and 62. The fasteners are tightened to mount the plug 16 as desired. Thebushings 60 and 62 assist in preventing compression of the molded plug16 upon tightening of the fasteners, and help maintain the shape andintegrity of the plug.

While the disclosure has been illustrated and described in detail in thedrawings and foregoing description, the same is to be considered asillustrative and not restrictive in character, it being understood thatonly certain embodiments have been shown and described and that allchanges and modifications that come within the spirit of the disclosureare desired to be protected.

1. A device configured to maintain an electric circuit in a fixedposition during an overmolding process, comprising: a wire retainerconfigured to hold an electric circuit in a fixed position while beingmolded within a molded item, the retainer having a first end and anopposite second end, wherein the retainer includes a first bushingdefining a mounting hole for the molded item extending along a widthaxis, wherein the bushing includes front and back surfaces configured tobe aligned and substantially co-planar with the front and back surfacesof the molded item; and a first securing member configured to secure aportion of the electric circuit to the retainer within the molded itemto hold the electric circuit in a fixed position within the molded itemduring the overmolding process.
 2. The device of claim 1, comprising asecond securing member configured to secure a portion of the electriccircuit to the retainer within the molded item.
 3. The device of claim1, comprising a second bushing adjacent the second end of the retainer,the first bushing being adjacent the first end of the retainer, whereinthe second bushing defines a second mounting hole for the molded itemextending along a width axis, wherein the retainer includes alongitudinal portion extending between the first and second bushingsalong a longitudinal axis, the width axis of the mounting hole beingsubstantially perpendicular to the longitudinal axis of the longitudinalportion.
 4. The device of claim 1, wherein the first and second securingmembers are wire ties configured to wrap around the longitudinal portionof the retainer as well as the first and second portions of the electriccircuit, respectively, to securely maintain the connection between theelectric circuit and the retainer.
 5. The device of claim 1, wherein thefirst and second securing members are sections of tape configured towrap around the longitudinal portion of the retainer as well as thefirst and second portions of the electric circuit, respectively, tosecurely maintain the connection between the electric circuit and theretainer.
 6. The device of claim 1, wherein the first and secondsecuring members are wire crimps configured to connect the first andsecond portions of the electric circuit to the longitudinal portion ofthe retainer to securely maintain the connection between the electriccircuit and the retainer.
 7. The device of claim 1, wherein the firstand second securing members are molded to the retainer.
 8. The device ofclaim 1, wherein the first and second securing members are integralcomponents of the retainer.
 9. A plug assembly, comprising: a moldedplug having opposing first and second ends and opposing front and backsurfaces, the plug extending along a longitudinal axis, wherein the plugincludes a socket extending from the front surface at least partiallythrough the plug along a width axis, the socket defining at least onehole extending at least partially therethrough; a retainer at leastpartially molded within the plug, the retainer having a first endadjacent the first end of the plug and a second end adjacent the secondend of the plug; a first wire set extending into the plug and connectedto the socket within the plug; and a first securing member securing thefirst wire set to the retainer within the plug, adjacent the first endof the retainer, to hold the first wire set in a fixed position withinthe plug during the overmolding process.
 10. The assembly of claim 9,comprising a second wire set extending into the plug and connected tothe socket within the plug, and a second securing member securing thesecond wire set to the retainer within the plug, adjacent the second endof the retainer, to hold the second wire set in a fixed position withinthe plug during the overmolding process.
 11. The assembly of claim 10,wherein the first wire set includes two wires, the second wire setincludes two wires, and the socket defines four holes, each hole beingassociated with one of the wires.
 12. The assembly of claim 9, whereinthe retainer is composed of a plastic material and the plug is composedof polyvinylchloride.
 13. The assembly of claim 10, wherein each of thefirst and second securing members is selected from the group consistingof a tie, a section of tape, a crimp and a clip.
 14. The assembly ofclaim 9, wherein the retainer includes a first bushing adjacent thefirst end of the retainer, defining a first mounting hole in the plugextending along a width axis, wherein the retainer includes alongitudinal portion extending from the first bushing along alongitudinal axis, wherein the bushing includes front and back surfacesaligned and substantially co-planar with the front and back surfaces ofthe plug.
 15. The assembly of claim 9, wherein the retainer includes afirst bushing adjacent the first end of the retainer, defining a firstmounting hole in the plug extending along a width axis, and a secondbushing adjacent the second end of the retainer, defining a secondmounting hole extending along a width axis, wherein the retainerincludes a reduced-height longitudinal portion extending between thefirst and second bushings along a longitudinal axis, wherein each of thebushings includes front and back surfaces aligned and substantiallyco-planar with the front and back surfaces of the plug, respectively.16. The assembly of claim 15, comprising first and second mounting boltsconfigured to be received in the first and second mounting holes tomount the plug.
 17. The assembly of claim 15, wherein the width axis ofthe first mounting hole, the width axis of the second mounting hole andthe width axis of the socket are substantially parallel, and wherein thelongitudinal axis of the retainer is aligned with the longitudinal axisof the plug and perpendicular to the width axes of the first mountinghole, the second mounting hole, and the socket.
 18. A method,comprising: providing an electric circuit; providing a retainerconfigured to hold the electric circuit in a fixed position within acavity of a molding die during overmolding of a portion of the electriccircuit to form a molded item, wherein the retainer includes at leastone built-in bushing defining a hole extending through the retainer, andwherein the retainer is configured to remain permanently molded withinthe molded item; permanently attaching the electric circuit to theretainer with at least one securing member; and overmolding at least aportion of the electric circuit and the retainer to form the molded itemcontaining a portion of the electric circuit and the retainer.
 19. Themethod of claim 18, wherein the at least one securing member includestwo wire ties each attaching a portion of the electric circuit to theretainer.
 20. The method of claim 18, wherein the at least one securingmember includes two wire crimps each attaching a portion of the electriccircuit to the retainer.
 21. The method of claim 18, comprising mountingthe molded item, wherein the retainer includes at least one built-inbushing and the end surfaces of the bushing are configured to contactinside surfaces of the molding die such that the built-in bushingdefines a hole extending through the molded item, wherein the mountingincludes inserting a bolt through the hole defined in the molded itemand tightening the bolt.
 22. The method of claim 18, comprising mountingthe molded item, wherein the retainer includes at least two built-inbushings and the end surfaces of the bushings are configured to contactinside surfaces of the molding die such that the two built-in bushingsdefine two holes extending through the molded item, wherein the mountingincludes inserting two bolts through the two holes defined in the moldeditem and tightening the bolts.
 23. The method of claim 18, wherein theovermolding includes positioning the retainer and a portion of theelectric circuit in the mold cavity of the molding die and filling themold cavity with molten plastic.